As I progress through the divorce and watch my relationship to stbx transform, I've been thinking a lot about why our attempt at R failed. Going beyond the obvious things, like continued or renewed cheating, what are some of the reasons that lead the BS to divorce?
In my case, I think it was a cascade of things. Each of the subsequent DDays hurt a lot, with the false R reveal probably being the most damaging, but that was only DDay2, and I invested in R quite a bit after that. We didn't even start MC until a couple months later, and we stayed in MC for about a month past DDay4 (DDays 3 & 4 were major trickle truths).
Even after all that, I tried to keep an open mind to the possibility that my WS would change in ways that made me feel safe. Ultimately, while he did a lot of work to understand himself and his behavior, while he tried to make himself "affair proof" in terms of boundaries with women, I think he still needs external validation, he still struggles with constructive criticism, and he still has issues with impulse control.
Meanwhile, I struggle mightily to forgive a lot of what he did during the affair years, but I think I could've built a new marriage with him if he could have really changed. I was strongly motivated to save our family and, being close to an early retirement, to save my vision of our future. But I also wonder if the degree of change I needed to see was humanly possible - it would've required an almost new personality.
I had a feeling the radical changes he made to save R would be temporary, and that turned out to be the case. I felt like he was doing them to prove something to me, not because it was intrinsically who he wanted to be, and now (a year later) his behavior shows that I was right - he's gone back to all the habits I dislike and doubled down on some of them. (The changes were to cut back on drinking and collecting alcohol, to stop smoking and collecting cigars, to reduce his spending in general, and to cut back on video games.)
While he continues to generally be kind and do me favors, he is also doing whatever he wants (as is his prerogative) so it's clear that what I wanted was never really what he wanted.
I think some other reasons that cause R problems for the BS (including me) is because the WS never gets out of defensive mode, or doesn't become truly humble, or continues to lie in other areas of their life. What else am I missing?